Tapeworm infections 

Introduction 

Humans can get a tapeworm infection by eating raw contaminated meat or fish.

Types of tapeworm

The tapeworms that most commonly infect humans include:

  • the pork tapeworm (Taenia solium)
  • the beef tapeworm (Taenia saginata)
  • the fish tapeworm (Diphyllobothrium latum)
  • the dwarf tapeworm (Hymenolepis nana)
  • the dog tapeworm (Echinococcus granulosus)

Some types of tapeworm, such as the pork tapeworm and the dog tapeworm, can cause other illnesses. This happens when tapeworm larvae (newly hatched worms) settle in places outside a person's intestine.

Tapeworms are parasites that can live in people's intestines (bowel). They belong to a class of worms called cestoda, so are known medically as cestodes.

Tapeworms tend to be flat, segmented and ribbon-like. Humans can catch them by:

  • touching contaminated faeces (stools) and placing their hands near their mouth
  • swallowing food or water containing traces of contaminated faeces
  • eating raw contaminated pork, beef or fish

See Tapeworm infections - causes for more information.

Getting help

If a tapeworm grows in your intestine, you will need treatment to get rid of it. Some adult worms grow to 4.5-9m (15-30 feet) in length.

You may not know that you have a tapeworm infection as it does not always cause symptoms, or the symptoms may be mistaken for another illness. A tapeworm infection typically causes stomach pain and sometimes vomiting and diarrhoea (see Tapeworm infections - symptoms for more information).

How common are they?

Tapeworm infections are most commonly seen in developing countries. In the UK, tapeworm infections in people are rare, although some types are found more often than others. For example, in 2005:

  • There were 71 reports of infection with the beef and pork tapeworms in England and Wales (although some infections may have been acquired abroad).
  • There were 11 cases of hydatid disease (caused by infection with the dog tapeworm) reported in England and Wales.

Outlook

The beef tapeworm lives only in your intestines and infection with it is easily treated with tablets.

However, infection with other tapeworms or tapeworm larvae can lead to serious complications (see Tapeworm infections - complications page). Larvae infections are more difficult to treat because the larvae will have settled in other parts of your body outside your intestines.

Last reviewed: 11/05/2010

Next review due: 11/05/2012